Description: This data was derived as part of the Overall Assessment of the State of Nearshore Waters. Across the Great Lakes, much of the nearshore, waters edge or back of beach has been altered with engineered structures or artificial material. Hardened shorelines reduce coastal resiliency by altering sediment dynamics, accelerating erosion, increasing water turbidity & destroying local vegetation. Shoreline hardening is assessed by determining the percent of the total length of shoreline in a Regional Unit that is hardened.The shoreline of LakeOntario and the St. Lawrence Riverhas been delineated as either "natural" or "hardened" based on the following definitions:Natural Shoreline: no engineered or aritificial structures in the nearshore, at the waters edge, toe of bluff, backshore or back of the beach; rising and falling water levels result in natural changes in the shoreline position; wildlife usage and vegetation migration upslope and downslope can occur unimpeded; natural vegetation communities, consistent with local conditions, are generally present along the shore.Hardened Shoreline: the nearshore, waters edge, toe of bluff, backshore or back of beach has been altered with engineered structures or artificial material (e.g. offshore breakwaters, lakefill, groynes, seawalls, revetments, dumped concrete rubble, artificial channels, dikes, etc.); natural shoreline processes are altered, and native vegetation communities are generally absent.Shoreline exposure is also attributed:Lake:shoreline directly exposed to lake wave energySheltered: shorelines with embayments, tributaries or the inside of jettied structures where there is protection from wave energy and currentsConnecting Channel: shorelines in the Great Lakes connecting channelsBest available, most recent aerial imagery was used for the delineation, at a scale of approximately 1:2,000. Low Stress: <25% shoreline hardeningModerate Stress: 25-50% shoreline hardeningHigh Stress: >50% shoreline hardening